Process for treating a liquid with a suspension of solids by passage thereof througha separator, regenerating the separated solids for re-use with untreated liquid



2,420. 761 OLIDS BY PASSAGE TED SOLIDS Patented May 20, 1947 Charles L.Thomas, Chicago, Ill, assignor to Universal Oil Products Company,Chicago, 111., a corporation of Delaware Application October 23, 1942,Serial No. 463,054

UNITED STATES PATENT OFFICE 3 Claims. 1

The present invention is concerned with a process for contacting solidswith liquids for the production of treated products by exchangereactions, and is characterized by effecting the contacts in movingstreams of liquids.

character of the liquid or the solid.

treated.

terial whenever this is economical.

the present invention is concerned.

(Cl. 19G-147) spent solid from the treated liquid in a zone of increasedcross-section and decreased flow rate by gravity, allowing the separatedsolid to settle countercurrent to an ascending stream of purilyingliquid to effect a partial purification there- 5 There are many types ofindustrial processes of, contacting the partially purified solid with inwhich liquids are contacted with granular further quantities of a washliquid which carries solids in order to effect a change either in thethe solid in suspension upwardly through a zone In most of whereinfurther reactivation of the solid occurs, these processes the granularmaterial constitutes separating the solid from the wash liquid by astationary bed through which the liquid to be gravity in a second zoneof decreased flow rate, contacted is passed either in an upward ordownallowing the solid to settle countercurrent to furward direction toeffect various types of exchange ther quantities of purifying liquid andreturning reactions. As examples of such solid-liquid conthe purifiedsolid to further contact with the tacts may be mentioned the passing ofoils, either primary liquid to be treated. or an animal, vegetable, orpetroleum origin, in The flow which characterizes the presentproccontact with granular adsorbents to efiect the ess of solid-liquidcontact will be described by refining of the oils through the adsorptionof reference to the attached drawing which shows undesirable colors,odors and tastes by the adin general side elevation an arrangement ofapsorptive action of the granular materials. In paratus in which theprocess may be effectively such cases, the granular materials mayinclude conducted. The drawing is diagrammatic and such substances asactivated carbons or chars. not drawn to any absolute or relative scale.l y vario s typ f f ll s r h. d n n A liquid to be contacted with agranular solid agents h as bauxite and Specially prepared is introducedthrough a line I containing a valve r nu r omp es of a mix a er. In zand recovered solid material is admitted to the Simila! y 8 Solutions ybe refined stream of liquid through a valve 24 which may y contact withgranular Chara Waters y be of any type found effective for separatingthe be treated to render them potable or improve purified solid from theliquid used in its purificathcir p p r r o m i uses y p sin tion. Theliquid to be treated passing into line 3 them through beds of eolites 0rpermutites is introduced at a, velocity sufilcient to carry which v t Pp y 0f exchanging alkali amounts oi? solid necessary for effecting thetreat metals for alkaline earth metals and thus soiment of the liquidand in the drawing the dotted toning and Otherwise p v g the Watersarrows indicate a suspension oi solid in liquid which rises upwardlythrough annular space 4' in In stationary bed operations of thecharacter treater 4. On entering upper section 5 the velocdescribed itis customary to pass a liquid through ity of liquid flow is reducedowing to the increased a stationary bed of granular solid until thetreatcross-section and the spent or partly spend solid ing capacity ofthe solid is spent, after which treating material settles by gravityinto inner the liquid undergoing treatment is diverted cylindrical tube9, while the treated liquid flows through a fresh bed of granular solidand steps upwardly and is recovered from overflow pipe 6. are taken forthe reactivation of the spent ma- Line 1 containing a valve 8 isprovided for the In such release of any gas which may accumulate.alternate bed processes the switching of the flow The spent solidtreating reagent then flows of the liquid undergoing treatment and theredownwardly by gravity countercurrent to an activation of the spentsolid may involve conascending stream of purifying or purging liquidsiderable manipulation of valves, either manually which is introducedthrough line H] containing or automatically. It is with an improvedmethvalve H, the rate of flow of this purifying fluid 0d of effectingsolid-liquid contacts which perbeing kept at a value which permits thesettling mits smoother and more definite operations that 01 the solid.The partly purified solid is then permitted to drop through valve I2into a fur- In one specific embodiment the present inther stream ofpurifying fluid admitted from line vention comprises a process fortreating liquids l3 containing valve l4 and the solid is then. withgranular solids which comprises passing a carried through line i5 intoannular space IS in suspension of solid in the liquid to be treatedupreactivator 16. During passage through the anwardly through a treatingzone. separating the nular space the wash liquid, which may be of thesame or different character than that employed in inner tube 9, effectsa further purification of the solid and upon entering upper section I!the liquid velocity decreases, the purifying liquid is recovered fromoverflow line i8, and the partly purified solid falls by gravity throughinner tube 2| against a final stream of purifying liquid introducedthrough line 22 containing a valve 23 at a rate permitting the settlingof the solid. Line l9 containing valve 20 permits the release of anyaccumulations of fixed gases in section H of the reactivator. Thepurified solid is then permitted to fall through valve 24 and again bepicked up by the stream of inlet liquid introduced through line i andrecycled.

The flow of the character described may be employed advantageously inthe treatment of lubricating oils with granular iullers earth orclay-like materials. Thus, the granular solid is carried up throughannular space 4' in treater 4 at some temperature found optimum forefi'ecting decolorizing or other treatment of the lubricating oil, thespent granular solid then overflows into tube 9 and may settledownwardly countercurrent to a wash liquid consisting of a lightpetroleum naphtha which removes traces of adhering lubricating oil sothat the lubricating oil and the naphtha pass out through line 5, thenaphtha being removed from the lubricating oil by subsequentdistillation. The granular claylike material then falls into the lowerpart of tube 9 through valve I2 and may be further extracted with a morepowerful solvent such as, for example, a mixture of benzol and alcoholor acetone which extracts adsorbed impurities of a polymerized orasphaltic character coating the solid particles, these impurities notbeing removed by the naphtha. While flowing through annular space It,the solvent mixture may effect substantially complete extraction ofimpurities and in section I! of the reactivator, the solution containingthe extracted impurities is separated from the solid and is removedthrough line [8 from whence it may be sent to a solvent recovery system.In falling through inner tube 2|, the solid treating reagent may fiowcountercurrent to a final solvent liquid and then pass through valve -24into a lower section of tube 2| to further treat the lubricating oilintroduced through line I.

The flow shown may also be used for softening waters by the use of baseexchange zeolites, in which case a hard water introduced through line Iwill carry the activated zeolite upwardly through line 3 and annularspace 4' in treater 4. The softened water and the spent zeolite willseparate in section 5 with the water recovered through line 6 and thegranular zeolite falling downwardly in tube 9 against a rising stream ofsoftened water. The zeolite passing through valve I2 will then meet astream oi salt solution introduced through line i3 and in passingthrough line i5 and annular space l5 of reactivator IS, the sodium ofthe salt solution enters the zeolite and the alkaline earth bases enterthe liquid as chlorides. The zeolite and wash liquid are separated insection 11, the wash liquid passing out through line i8 and the zeolitesettles by gravity through tube 2i countercurrent to a slowly ascendingstream of liquid introduced through line 22 which may be a softenedwater. The zeolite passing through valve 24 is then in condition tofurther soften the stream of water introduced by way of line I.

In an application of the present process flow silica hydrosols may beproduced by continuously contacting solutions of alkali metal silicateswith hydrogen exchange zeolites which are made by treating ordinaryzeolites or special carbonaceous zeolytic materials with mineral acids.In such cases the fiow will generally be similar to that just describedfor softening hard waters with granular zeolites but the liquidrecovered from section 5 of the treater will constitute the silicahydrosol, while the zeolite will then contain the alkali metal and besubject to washing in tube 9 and annular space IS with mineral acids toreplace sodium with hydrogen.

In a further modification of the process flow the sodium ions present insilica-alumina type composites made by compositing alumina in variousways with silica produced by the acidification of alkali metal silicatesolutions may be treated for the removal of sodium by contacting themwith ammonium salt solutions, using the general type of flow alreadydescribed. After this operation the silica-alumina composites are heatedto drive out ammonium salts and then, if otherwise properly prepared,are ready for use in catalysts for hydrocarbon conversion reactions.

I claim as my invention:

1. In the treatment of a liquid with a subdivided solid, the methodwhich comprises introducing a suspension of the solid in the liquid tothe lower portion of a first contacting zone and passing the suspensionupwardly through said zone, separating solid particles by gravity fromthe treated liquid in an upper region of said zone, removing the treatedliquid from said zone simultaneously passing a stream of purifyingliquid upwardly in a confined path within said zone, passing theseparated particles downwardly by gravity through the ascending streamof puritying liquid, thereafter suspending said particles in additionalpurifying liquid and passing the resultant suspension upwardly through asecond zone, separating thus treated solid particles by gravity fromsaid additional liquid in an upper region of the second zone,simultaneously passing a second stream of purifying liquid upwardly in aconfined path within said second zone, passing said treated solidparticles downwardly by gravity through said second ascending stream ofpurifying liquid, and then returning the solid particles to thefirst-mentioned zone in suspension in a further quantity of the liquidto be treated.

2. In the refining of hydrocarbon oil by treatment thereof withparticles of solid adsorbent material to remove impurities from the oil,the method which comprises passing a suspension of the solid adsorbentparticles in the oil upwardly through a treating zone, separating solidparticles containing impurities from the treated oil by gravity in anupper region of said zone, passing the separated particles downwardly bygravity through an ascending stream of wash liquid for adheringhydrocarbons, thereafter suspending the solid particles in a liquid.solvent for adsorbed impurities and passing the resultant suspensionupwardly through a second zone, separating thus treated particles bygravity from said liquid solvent in an upper region of the second zoneand passing the same downwardly by gravity through an ascending streamof additional liquid solvent, and then returning the solid particles tothe firstmentioned zone in suspension in a further quantity of the oilto be refined.

3. A process for producing a silica hydrosoi which comprises passing asuspension or a hydrogen exchange zeolite in a solution of an alkalimetal silicate upwardly through a treating zone wherein said silica so]is produced by exchange of alkali metal for hydrogen, separating thezeolite from the silica. sol by gravity in an u per region of said zone,passing the zeolite downwardly by gravity through an ascending stream ofwater, thereafter suspending the zeolite in an acid solution and passingthe resultant suspension upwardly through a second zone wherein thehydrogen exchange zeolite is regenerated, separating the regeneratedzeolite by gravity from the regenerating solution in an upper region ofsaid second zone and passing the same downwardly by gravity through awashing liquid to remove the regenerating solution, and then returningthe regenerated zeolite to the firstmentioned zone in suspension in anadditional quantity of the solution or alkali metal silicate. CHARLES L.THOMAS.

REFERENCES CITED The iollowing references are of record in the file ofthis patent:

Number UNITED STATES PATENTS Name Date Higgins Feb. 4, 1930 Neumann July15, 1930 Nordell Nov. 30, 1926 Green Apr, 1, 1930 Hodkinson June 17,1930 Hoclkinson June 17, 1930 Pick June 4, 1935 Baskerville Oct. 20,1914 Ayres, Jr Mar. 18, 1919 Chenault et al June 8, 1943 Chenault et al.June 8, 1943 Chenault et a1. June 8, 1943 Scheineman Feb. 8, 1944 Deaconet a]. Nov. 7, 1911 Bramwell Mar. 8, 1927 Bird June 3, 1941

